Henry's law and hydrolysis-rate constants for peroxyacyl nitrates (PANs) using a homogeneous gas-phase source

Abstract

The solubilities and hydrolysis rates of PAN (peroxyacetyl nitrate) and its homologues PPN (peroxypropionyl nitrate), PnBN (peroxy-n-butyl nitrate), PiBN (peroxy-isobutyl nitrate) and MPAN (peroxymethacryloyl nitrate) in liquid water have been studied at 20 °C. Temperature dependencies were measured for PAN and PPN. The solubilities of peroxyacyl nitrates decrease smoothly with increasing carbon-chain length fromH (293 K)=4.1 M atm−1 (PAN) toH (293 K)=1.0 M atm−1 (PiBN). Hydrolysis-rate constants, which cover the range fromk h (293 K)=(2.4−7.4)×10−4 s−1, do not show a systematic chain-length dependency. Solubilities of PAN and PPN in solutions which mimic the composition and ionic strength of sea water are 15% and 20% lower than in pure water. The hydrolysis rate constants are not affected.